Here's what the the genyoooowine Vitus cable guide looks like:

Used on both the 979 and Carbone models as I think they share the same CLB BB shell design. The one in the pic is what is on my Vitus Carbone 7.
Hope you eventually find one for your bike!
BTW, the hole you see right next to the word "Depose" (above it on the pic) is actually where the stud is that goes into the BB to locate the guide properly. It is hollow so it can doulbe as the drain hole for the BB if water gets in. These cable guides usually get lost/separated from the frames when a seller dismantles the Vitus bike and unintentionally takes it away from the bike with the derailleurs and cables as the guide clips on to the cables with the small tangs you see in the guide's grooves. So it is always good to check if the guide is still with the frame if one is considering buying a Vitus 979 or Carbone frameset.

Chombi